Soccer heading
associated with white matter microstructure and cognitive abnormalities

Lipton
ML., Kim N., Zimmerman ME., Kim M., Stewart WF., Branch CA.  Radiology. 2013; ahead of print

Take Home Message: Heading was associated with abnormal
white-matter microstructure and poorer neurocognitive performance.
History of concussion was not associated with altered structure.

Long-term cognitive impairments
following repeated sport-related head injury is a major concern. However, the role
of subconcussive impacts from soccer heading as an additional mechanism of
cumulative brain injury has not been well examined. If repetitive heading
causes adverse effects on the brain there could be additional rules put in
place to prevent long-term consequences. Therefore, the purpose of this study
was to investigate the association of soccer heading with evidence of traumatic
brain injury. Twenty-eight male and 9 female amateur soccer players completed
the
Einstein Heading Questionnaire. The Einstein
Heading Questionnaire was used to estimate heading during the prior 12 months
as well as ascertain participants’ demographics and lifetime concussion
history. Then a licensed neuropsychologist conducted a neuropsychological
assessment to measure psychomotor speed, attention, executive function, and
memory. Finally, whole-brain
magnetic resonance imaging was performed. Using the data taken from the Einstein
Heading Questionnaire the authors determined that the number of headings ranged
from 32 to 5400 times during the previous year. To assess the relationship of
heading and participant characteristics researchers separated the participants
into 3 exposure groups: nine participants were in the low-heading group (
£ 276 headings a year), 19 participants were classified in
the medium-heading group (277 to 1095 headings per year), and nine were placed
into the high-heading group (
³ 1096 headings per year). Higher
levels of heading were associated with more months of playing per year. There
was no difference in groups with respect to age, years of education, or
concussion history. Imaging revealed an association between heading and amount
of white matter microstructure damage within 3 locations of the
temporal-occipital region with a threshold value from 885 to 1550 headings per
year. There was also an association between heading and memory function with a threshold
of approximately 1800 headings per year. There were no other significant
relationships found between imaging and cognitive measures.

This study suggests a relationship
between the number of self-reported headings with abnormal white matter microstructure
and poorer neurocognitive performance on a memory test. Interestingly, there
were no relationships associated with previous concussion. Additionally, there
were estimated heading thresholds (885-1550 headings associated with abnormal
white matter microstructure; 1800 headings associated with memory impairments).
It has been proposed that athletes can recover from a concussion given enough
time. This study suggests that brain tissue is injured with sub-concussive
impacts and that the white matter is unable to repair itself beyond a certain
level of heading exposure. There are some notable limitations within this study.
For example the heading exposure was self-reported, and there was no
consideration for site of impact, velocity, or other individual heading
characteristics.

Questions for Discussion: Do you think placing rules on heading
count limits would help prevent concussions? How would this be monitored?  Do you think youth athletes are more at risk?

Written by: Jane McDevitt PhD, ATC,
CSCS
Reviewed by: Stephen Thomas

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Lipton ML, Kim N, Zimmerman ME, Kim M, Stewart WF, Branch CA, Lipton RB. (2013). Soccer Heading Is Associated with White Matter Microstructural and Cognitive Abnormalities Radiology DOI: 10.1148/radiol.13130545